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Removing Old Steel Water Pipe & Replacing It With New PEX Piping

If you have an older home built before the 1980s, you’re probably dealing with old steel piping in the kitchen and bathrooms.

Replacing it with PEX will be much better in the long run and prevent pipes from rusting and bursting. But how do you replace old steel pipes with PEX? I’ll show you!

Why is Old Steel Piping Bad?

It was a plumbing marvel when it was first invented in the early 1900s. But today, steel water pipes are a hazard in your home. They rust, corrode and break.

One of the first houses I bought and flipped was built in 1948 and had steel pipes in the bathroom. But the bathroom had to be dealt with. Thankfully, the kitchen had been converted before I took over.

As we took out the old pipes, we saw just how corroded they were and realized that it would have only been a matter of a few months before we had issues.

What is PEX Piping?

PEX piping, or cross-linked polyethylene piping, is a plastic piping commonly used in residential and commercial plumbing systems. PEX piping is made from high-density polyethylene (HDPE) and is treated with a chemical process called cross-linking, increasing its strength and durability and making it great.

What I love the most about PEX piping is that it’s super flexible, so it’s easy to install and maneuver around obstacles in the walls and floors of a building. This flexibility also helps to reduce the number of fittings and connections you need, which can lead to fewer potential leak points in the walls of your home.

It’s also resistant to corrosion, doesn’t develop pinholes as copper or steel pipes do, doesn’t scale or pit like metal pipes, and can withstand high temperatures and pressures.

Another advantage of PEX piping is that it’s relatively cheap compared to other types of piping, especially considering all the benefits you get with it. And it’s available in different colors, which makes it easier to identify the type of water inside the pipe (hot or cold).

But PEX piping isn’t recommended for outdoor use because it can become brittle in cold temperatures and may not be great for use in areas with high UV exposure. Sunlight degrades and breaks it down over time.

Pros and Cons of PEX Piping

Like anything, there are always pros and cons before making massive changes to your home.

Pros of Using PEX Piping

  • Flexibility: PEX piping is flexible, which makes it easy to install and maneuver around obstacles in the walls and floors of a building. This flexibility also helps reduce the number of fittings and connections required, leading to fewer potential leak points.
  • Durability: PEX piping is resistant to corrosion and does not develop pinholes like copper pipes. It also does not scale or pit like metal pipes and can withstand high temperatures and pressures.
  • Cost-effective: PEX piping is relatively inexpensive compared to other types of piping.
  • Different colors availability: PEX piping is available in different colors, making it easier to identify the type of water inside the pipe (hot or cold). You can even get varying sizes.

Cons of Using PEX Piping

  • Not for outdoor use: PEX piping, while great for inside your home, can become very brittle in lower temperatures.
  • Can break down in UV light: PEX piping is not UV resistant and will degrade if exposed to UV light for long periods.
  • Hard to repair: PEX piping can be hard to fix if a leak occurs, as the entire section of the pipe may need to be replaced. With that being said, it’s hard to damage.
  • Not for high-pressure systems: PEX piping is not great; it cannot withstand pressure.
  • Not recommended for chemicals: PEX piping doesn’t mix well with certain chemicals, like chlorine or chloramines.

Reasons to Remove Old Steel Water Pipes

  1. Corrosion: Steel pipes are susceptible to decay over time, which can cause rust and other debris to build up inside the lines. This can lead to reduced water flow, leaks, and even pipe failure.
  2. Leaks: Steel pipes can develop leaks over time, which can cause water damage and mold growth in the walls and floors of a building.
  3. Low water pressure: As steel pipes age, they become clogged with rust and other debris, which reduces the water pressure in the building.
  4. Health concerns: Rust and other contaminants can also leach into the water supply, causing health risks to you and your family if that’s where you get your drinking water.
  5. Inefficiency: Old steel pipes can be less energy efficient than newer materials, such as PEX piping, leading to higher water heating costs.
  6. Difficulty to repair: Old steel pipes can be challenging to improve, as they may need the replacement of entire pipe sections or multiple fittings and connections.
  7. Outdated: Steel pipes are considered an obsolete material, and, in some areas, it’s not allowed to use steel pipes for new installations anymore.

Replacing old steel water pipes with newer materials like PEX piping can help to prevent leaks, improve your overall water pressure, and reduce the risk of contamination. It can also help to improve energy efficiency and reduce maintenance and repair costs for your home in the long run.

How to Remove Old Steel Water Pipes and Replace with New PEX Piping

  1. Turn off the water supply where the pipes need to be replaced. This can typically be done by turning off the main water supply valve for the house.
  2. Drain any remaining water from the pipes by turning on all the faucets and flushing the toilets.
  3. Use a pipe cutter or saw to cut the steel pipes where the new PEX pipes will be installed. Wear safety gear like goggles and gloves to protect yourself from metal shards.
  4. Use a pipe wrench to loosen and remove any fittings or connections holding the old pipes in place.
  5. Carefully remove the old steel pipes from the area. Dispose of them properly.
  6. Measure the length of the new PEX pipes needed and cut them to the appropriate size.
  7. Use a PEX pipe cutter or scissors to make the cuts.
  8. Insert the new PEX pipes into the fittings and connections removed in step 4. Then use a PEX cinch clamp or crimp ring to secure the pipes.
  9. Turn your water supply back on so you can check for any leaks. Make any necessary adjustments to the connections.
  10. Turn on the faucets and check for any leaks or issues.

Final Words on PEX and Steel

This is just a general guide, and specific steps can vary depending on the type of piping you’re replacing, the location of the pipes, and your level of experience. Also, I highly recommend you hire a professional plumber if you’re not confident in your abilities to do a job like this.